Typical machines for binding a package with a loop of flexible strapping material are described in the U.S. Pat. Nos. 1,357,883; 3,146,694; 3,215,064; 3,636,861; 3,691,939; 3,875,855; 3,916,779; and 3,946,659. These types of machines incorporate strap guide structures of various kinds to guide the strap in a loop around the package to be bound.
Disclosures have been made of machines which first form a small loop in a certain manner and which then enlarge the loop to fit around the package to be bound. In the past, Signode Corporation, the assignee of the entire interest of the present invention, has developed several processes and machines for forming a strap loop about a package, tensioning the loop, and finally joining the overlapping portions of the tensioned loop.
Some of these processes and machines, such as those disclosed in the U.S. Pat. Nos. 4,062,278, 4,077,313, and 4,079,667, involve the initial formation of a small, primary strap loop in or around a circular guide and then the subsequent expansion of the primary loop to a larger diameter for fitting around the package. The process is then completed by tensioning the loop about the package, joining the overlapping strap portions, and severing the secured loop from the trailing portion of the strap.